Portuguese police investigating the disappearance of Madeleine McCann exactly 12-years ago, have identified a potential new suspect, it has been claimed, as her parents vowed to carry on the search "for as long as it takes".

Per reports in the Daily Mail, authorities have received a tip-off from Scotland Yard about a foreign paedophile who was in Portugal in May 2007, when the youngster disappeared from a resort.

Lisbon-based newspaper Correio da Manha asked to see materials relating to the case, but prosecutors refused, on the basis that they are pursuing "active lines of investigation".

Scotland Yard launched its own investigation into the disappearance, Operation Grange, after the much-maligned probe in Portugal came to a standstill - with a cost of over £12 million to United Kingdom taxpayers so far.

McCann's parents Kate and Gerry refused to participate in the documentary, on the basis that it could potentially hinder the active police investigation.

The couple will attend a church service near their home in Rothley, Leicestershire this afternoon to mark the sad anniversary.

The months and years roll by too quickly; Madeleine will be sixteen this month.

"A very small team continues to work on this case with Portuguese colleagues and we have put in an application to the Home Office for further funding".

When they arrived home that evening about an hour later, Kate said she at first didn't realize that her daughter was missing.

"Madeleine will be 16 this month". It's impossible to put into words just how that makes us feel.

Metropolitan Police Commissioner, Cressida Dick, said there were still "active lines of inquiry" being pursued by officers based at Scotland Yard and the Home Office is now considering whether to fund its operations for another year.

"There is comfort and reassurance though in knowing that the investigation continues and many people around the world remain vigilant".